Oral hygiene is one of the most accessible and well-known strategies for the prevention of dental caries. The benefits of this practice after tooth eruption are well established in the literature. Oral hygiene in newborns prior to tooth eruption is controversial, since there is a disagreement between the Dental and Pediatric Associations as to the optimal time to initiate oral hygiene in children and scientific studies in this regard have not yet been performed. Some of these associations recommend starting this practice from the eruption of the child's first tooth. Others recommend beginning the cleansing of the child's oral cavity from birth by cleaning the baby's gingival rollers and tongue. The aim of the present investigation will be to evaluate, through a randomized clinical trial, the influence of oral hygiene in newborns on Candida spp colonization. and on the child's behavior during oral hygiene after tooth eruption. Will be included in the study, pairs of mothers and babies born in the maternity of the Hospital Nossa Senhora da Saúde, in Diamantina, Minas Gerais, Brazil.

This will be a rehearsal Randomized clinical trial in which newborns will be allocated into 2 groups, namely:

• Newborns whose parents will receive guidelines for oral hygiene before tooth eruption (Group 1);
• Newborns whose parents will receive instructions not to perform oral hygiene before tooth eruption (Group 2).

The initial data collection will be performed one month after the child's birth and will include oral clinical examinations, saliva collection and questionnaires on the socio-environmental, economic and behavioral aspects of the child and his family. Initial oral clinical examinations will be performed to assess the presence of Candidiasis, and saliva collection will be performed to identify and quantification of Candida spp. These evaluations will be performed again every three months. From the eruption of the first deciduous tooth, the follow-up included an assessment of the baby's behavior during oral hygiene performed by the responsible. This evaluation will be made by the examiner using the Frankl scale and HBCD scale criteria. Statistical analysis will be performed using the Statistical Package for Social Science, version 23.0 and will include descriptive, bivariate and multivariate analyzes.

Project presentation:

Primary Objective:

To evaluate the influence of oral hygiene of newborns before dental eruption on colonization by Candida spp. and about the baby's behavior during oral hygiene performed by parents after tooth eruption.

Secondary Objective:

To evaluate the influence of oral hygiene of newborns before tooth eruption on Candida spp colonization and occurrence of candidiasis during the follow-up period. To evaluate the influence of oral hygiene of newborns before tooth eruption on the its behavior during oral hygiene performed by parents after tooth eruption.

Proposed Methodology:

Study design: Randomized blinded clinical trial in edentulous newborns who will be screened in their first two days of life at the Maternity Hospital of Our Lady of Health in Diamantina, Minas Gerais. If mothers agree to participate with their child in the study, contact and address will be requested for further data collection that will be performed at the participants' homes.

Intervention Groups:

• 1. Mothers will be instructed to sanitize the newborn's oral cavity prior to tooth eruption by massaging the gingival rods with gauze and filtered water once a day at night. Following the eruption of the child's first tooth, mothers will be instructed to brush twice daily with fluoride toothpaste (1100 ppm fluoride) in a minimum amount, equivalent to one grain of raw rice, using the Fones technique .
• 2. Mothers will be advised not to perform any type of oral cavity cleaning of the newborn before tooth eruption. Following the eruption of the child's first tooth, mothers will be instructed to brush twice daily with fluoride toothpaste (1100 ppm fluoride) in a minimum amount, equivalent to one grain of raw rice, using the Fones technique .

The calculation of the sample size was obtained from Lee, Laboratory of Epidemiology and Statistics, using the calculation of estimation of two proportions and adopting the parameters proportion of cases (positive behavior during hygiene according to the Frankl Scale) among the exposed (children receiving oral hygiene before tooth eruption): 65% (unpublished data from a previous study by the research group); Confidence level (1 -) = 95%; (= 0.05 or 5%); Test power (1-) = 80%; Relative risk: 1.5; Newborns by group: 42; 9 newborns (20%) will be added to each group to compensate for possible losses. Thus, the sample required for the development of the study will be 51 newborns and their mothers in each of the groups.

The work team will be composed by the Researcher 1, Examiner 1 and Assistants. Prior to the start of the study, these researchers will undergo a training and calibration process according to the role of each team. A pilot study will be performed on 10% of the sample, and if no methodological changes are required, these children will be included in the main study. Randomization will be performed by allocating participants in both intervention groups through a computer-generated random number. Examiner 1 will be blind to the group in which the examined children were allocated and the mothers will be advised not to disclose the group in which they were allocated.

Data Collection and Follow-up Instruments:

Social, Environmental, Behavioral and Health Data Form general of children.

Registration form for colonization evaluation of Candida spp.

Through the identification and quantification of Candida spp. using CHROMagar Candida culture medium. This evaluation will be performed in the first month and at 4 months after the birth of the child. Form for registration of the child's oral clinical examination to record the presence and / or absence of Oral Candidiasis, and if present, its location. After the eruption of the first tooth the examiner will classify the child's behavior according to the Frankl Scale and HBCD Scale using the child's behavior record form that will be used for the period. follow-up at 1 month, 4 months, 7 months, 10 months and 13 months. The child's diet will be assessed through eating habits at all follow-up times through 24-hour dietary reminders using the multi-pass method.

Risks:

The risks inherent to the study are related to the awkwardness of the guardian during the clinical evaluations and / or examinations in the babies, as well as the possible discomfort of the child during the oral clinical examination. However, examiners will be prepared to identify any possible discomfort and minimize or disrupt the assessment if necessary. The application of questionnaires to those responsible will be performed in the presence of the same, in order to reduce their embarrassment. The information collected will be accessible only by members of research.

Benefits:

The benefits to patients will be oral health guidelines, follow-up of children by the examiner and, if necessary, referral for dental treatment. For health professionals, the research will provide scientific evidence and support for guidance to the population that will benefit from such recommendations with better care for children's oral health and consequent improved oral health-related quality of life.

Inclusion Criteria:

• Newborns who do not yet have erupted teeth at the time of the first assessment (1 month after birth).
• Newborns whose mothers agree with their participation and that of their child in the study.

Exclusion Criteria:

• Newborns who present with systemic impairment at the time of the first evaluation (1 month after birth), such as physical, neurological, respiratory diseases, gastroesophageal reflux disease, among others that may alter the oral microbiota.

Blindness The interventions will always be made by the same researcher and will not participate in the evaluations.

Examiner 1 will be blinded to the group in which the examined children were allocated. Mothers will be advised not to disclose the group in which they were allocated during the evaluations.